Coating composition



7 Patented Sept. 5, 1944 UHUW COATING COMPOSITION John Waldo Clough,Parlin, N. J., assignor to E. I. du Pont de Nemours Sp-Company,Wilmington,- Del., a corporation of Delaware No Drawing. ApplicationOctober 9, 1941, Serial No. 414,287

14 Claims. (CL 106-476) This invention relates to a means for preventingdirt collection and discoloration from that source in cellulosederivative finishes and more particularly to an improved bowling pincarrying a coating of a cellulose derivative finish which is highlyresistant to dirt collection.

Commercial practice for finishing bowling pins provides for theapplication of two or more coats of a cellulose nitrate composition byconventional spraying or dipping operations. The cellulose nitratecoating composition may consist of cellulose nitrate plasticized orsoftened with a minor proportion of castor oil. The inclusion of a resinexcept in very minor proportions is generally avoided because of agreater tendency of compositions containing such materials to increasedirt pick-up. The use of appreciable amount of plasticizer or softeneris not acceptable for the same reason. Bowling pins through the severeimpacts encountered from several sources in their customary use and thefriction occasioned by the rolling and spinning of the pin on the alleysurface and in the pit at the end of the alley become badly discolored,particularly at the area of maximum circumference, by embedded dirtpicked up through the aforementioned causes. Visibility is thus greatlyreduced and the pins are then discarded or must be cleaned or refinishedafter short usage.

The present invention, therefore, offers a marked advance in thisdirection in practically eliminating th defect of dirt collection durinthe normal life of a bowling pin.

A primary object of the invention is the provision of a means forpreventing dirt pick-up of articles coated with a cellulose derivativefinish, particularly such articles as may be exposed to impact and/orfrictional forces when dirt and grit may likewise be present. Anotherobject is the provision of a cellulose derivative coating compositionwhich provides a tough, adherent film resistant to the pick-up of dirtand the retention thereof in the finish surface to cause unsightlydiscoloration. A further object is the provision of an improved bowlingpin which does not become discolored by dirt collection, therebymaintaining good visibility and greatly extending the useful life of thepin. Other objects will appear as the description of the inventionproceeds.

These objects are accomplished by the incorporation in a substantiallyresin-free cellulose derivative coating composition of an agent whichfunctions to directly resist dirt collection and the subsequentretention thereof in the surface of the finish of articles coated withthe improved composition when such articles are subjected to impactand/or frictional forces in the presence of dirt particles.

The following examples are given by way of illustration only and nolimitations are intended thereby except as indicated in the appendedclaims.

This composition which contains a proportion of white pigment wasemployed as an intermediate coating in the system used in finishingbowling pins as hereinafter described.

Petroleum naphtha 10.400 Cetyl pyridinium bromide .014

In the finishing of bowling pins a suitable preferred system includesfirst the application of one coat of a penetrating primer of the typedescribed in a co-pending Overholt application, S. N. 296,- 762, filedSeptember 27, 1939. One coat of Example 1 is then sprayed over theprimer after it -500 lines.

has dried and this is followed by a final top coat of Example 2.

Several bowling pins were sprayed over the entire surface with one coatof a penetrating primer of the following composition:

Per cent by weight The polyvinyl butyral resin used in this example wascharacterized by a viscosity at 25 C. of about 3000 centipoises in thefollowing formula:

Per cent by weight Polyvinyl butyral resin 20 Denatured ethyl alcohol 52oluene 28 After the primer coat had dried, one coat of the compositionof Example 1 was sprayed over one-half of the surface of bowlingpinsdivided through the vertical axis and after this coating had dried, afinal coating of the composition of Example 2 was sprayed over thecoating from Example 1. The remaining half of the surface of bowlingpins already coated with the above described primer was sprayed with onecoat of a composition identical with that of Example 1 except that thecetyl pyridinium bromide ingredient was omitted and with a top coatidentical with Example 2 except for the omission of the cetyl pyridiniumbromide.

These pins were then tested in an automatic bowling alley for a serviceperiod amounting to Examination of the pins after this test showedsurprising superiority for the new system in that the surface areafinished with the compositions containing the cetyl pyridinium bromideshowed practically no dirt pick-up with no resultant discoloration anddecrease in visibility whereas in the surface area finished with theunmodified compositions, dirt collection near the point of greatestcircumference Where impact and friction forces are mostly encountered,was severe. The' dirt particles were embedded in the finish, making thecontamination diflicult if not impossible to remove, thus necessitatingcomplete refinishing of the pin for any further service.

The particular system given above for the finishing of bowling pinsrepresents a commercially acceptable system. However, the invention isnot limited thereto since the sequence of steps and the character of thecompositions may vary considerably. In some instances, the finishingsystem may require the use of clear vehicles for the complete finish andin others, the finish may be entirely pigmented. The number of coats mayalso be varied and other types of primers or sealers may be used. It isessential, however, that at least the top coat include as an essentialingredient an anti-dirt collecting agent of the type herein described inorder to secure the stated advantages of the invention.

Other similar tests using cellulose derivative compositions containinglauryl pyridinium chloride as the anti-dirt collecting agentconclusively showed that this material was as equally effective as theagent suggested in the examples and may be directly substituted therein.In general halides of aliphatic long chain derivatives of heterocyclicnitrogen bases in which the aliphatic radical contains at least 8 carbonatoms and is linked directly to the nitrogen atom, such as de scribed inU. S. Patent 2,192,956, are useful in the present invention. Compoundsof this type containing between 10 and 18 carbon atoms are preferred.Cetyl pyridinium iodide, hexadecyl pyridinium bromide, octa-decylpyridinium bromide and dodecyl pyridinium chloride are representative ofthe class of agents that may be employed. Cetyl pyridinium bromide andlauryl pyridinium chloride have proven to be particularly effective.

In the examples, the agent is present in an amount of 0.1% by weight ofthe total solids of the composition. Satisfactory results may beobtained, however, in amounts ranging from about 0.02% to 0.2% by weightof the total solids content of the composition although in general it ispreferred to use about 0.1% of the agent based on the total solidscontent of the coating composition. Amounts greater than 0.2% can betolerated but no particular advantage becomes apparent with higherproportions.

The invention is useful with other cellulose derivative compositionsincluding cellulose ethers, cellulose acetate and the mixed celluloseesters. The compositions may also contain coloring matter or not asdesired.

In the claims the term "cellulose derivative" is used in its commonlyaccepted sense in the art and includes derivatives which are inherentlywater-insoluble and produces tough, durable films.

As indicated in the examples, best performance is secured when thecompositions are free of resin but if it is desired to includeingredients of this type, the amount should be very small. Plasticizersand/or softeners may be employed in the new compositions but for bestresults, this type of ingredients should also be kept at a minimumproportion, preferably for 10 parts of cellulose nitrate from betweenabout 2 and 4 parts of plasticizer. The optimum ratio is 10 parts ofcellulose nitrate to about 3 parts of plasticizer.

The invention is broadly useful in the finishing of articles Where anysubstantial amount of dirt collection cannot be tolerated. It isparticularly and importantly useful where the finished article issubjected to impact and/or frictional forces in the presence of dirtparticles such as is encountered in the normal usage of bowling pins andit is to this utility that the present invention is particularlydirected. The compositions are also of merit in the finishing of woodenhandles and spinning bobbins where frictional forces are alsoencountered.

The primary advantage of the invention resides in the surprisingresistance to dirt pick-up by surfaces coated with compositionscontaining small quantities of the agents herein described. Articlesfinished with these compositions have a longer useful life. The originalvisibility of articles carrying the modified compositions is retainedfor extended periods of time since there is practically no contaminationor discoloration from dirt collection. The incorporation of smallamounts of the anti-dirt collecting agents does not in any way detractfrom the normal appearance or durability of the finish. Bowling pinsfinished in accordance with the present invention are outstandinglysuperior in service when compared to pins finished with conventionalsystems.

It is apparent that many widely different embodiments of the inventionmay be made without w! VII lIwv-uv .gHSCELLANEOUS PRODUCTS.

departing from the spirit and scope thereof; and, therefore, it is notintended to be limited except as indicated in the appended claims.

I claim:

1. An improved substantially clear coating composition particularlyadapted for finishing bowling pins and the like, comprising a cellulosederivative selected from the o p o t n of cellulose esters and celluloseethers and an antidirt collecting agent consisting of a halide of analiphatic long-chain derivative of a heterocyclic nitrogen base in whichthe aliphatic radical is linked directly with the nitrogen atom, saidcomposition being substantially resin-free.

2. Composition of claim 1 in which the cellulose derivative is cellulosenitrate.

3. Composition of claim 1 in which the antidirt collecting agent iscetyl pyridinium bromide.

4. Composition of claim 1 in which the antidirt collecting agent islauryl pyridinium chloride.

5. Composition of claim 1 in which the aliphatic radical in theanti-dirt collecting agent contains between 10 and 18 carbon atoms.

6. Composition of claim 1 in which the antidirt collecting agent ispresent in an amount between about 0.02 and 0.2% by weight of the totalsolids content of the composition.

7. An improved substantially clear coating composition particularlyadapted for finishing bowling pins and the like, comprising cellulosenitrate, a plasticizer for the cellulose nitrate in the proportion ofabout 3 parts of plasticizer for each 10 parts of cellulose nitrate andan antidirt collecting agent consisting of a halide of an aliphatic longchain derivative of a heterocyclic nitrogen base in which the aliphaticradical is linked directly with the nitrogen atom, said compositionbeing substantially resin-free.

8. An improved bowling pin highly resistant to dirt pick-up carrying asa surface coating a cellulose derivative composition comprising asubstantially clear cellulose derivative selected from the classconsisting of cellulose ethers and cellulose esters and an anti-dirtcollecting agent consisting of a halide of an aliphatic long chainderivative of a heterocyclic nitrogen base in which the aliphaticradical is linked directly with the nitrogen atom.

9. An improved bowling pin highly resistant to dirt pick-up carrying asa surface coating a cellulose derivative composition comprising asubstantially clear cellulose derivative selected from the classconsisting of cellulose ethers and cellulose esters and an anti-dirtcollecting agent consisting of a halide of an aliphatic long chainderivative of a heterocyclic nitrogen base in which the aliphaticradical contains at least 8 carbon atoms and is linked directly with thenitrogen atom.

10. An improved bowling pin highly resistant to dirt pick-up carrying asa surface coating a cellulose derivative composition comprising asubstantially clear cellulose derivative selected from the classconsisting of cellulose ethers and cellulose esters and an anti-dirtcollecting agent consisting of a halide of an aliphatic long chainderivative of a heterocyclic nitrogen base in which the aliphaticradical contains between 10 and 18 carbon atoms and is linked directlywith the nitrogen atom.

11. An improved bowling pin highly resistant to dirt pick-up carrying asa surface coating a cellulose derivative composition comprising asubstantially clear cellulose derivative selected from the classconsisting of cellulose ethers and cellulose esters and an anti-dirtcollecting agent consisting of cetyl pyridinium bromide.

12. An improved bowling pin highly resistant to dirt pick-up carrying asa surface coating a cellulose derivative composition comprising asubstantially clear cellulose derivative selected from the classconsisting of cellulose ethers and cellulose esters and an anti-dirtcollecting agent consisting of lauryl pyridinium chloride.

13. An improved bowling pin highly resistant to dirt pick-up carrying asa surface coating a cellulose derivative composition comprising asubstantially clear cellulose derivative selected from the classconsisting of cellulose ethers and cellulose esters and an anti-dirtcollecting agent consisting of a halide of an aliphatic long chainderivative of a heterocyclic nitrogen base in which the aliphaticradical is linked directly with the nitrogen atom in-an amount between0.02% and 0.2% by weight of the total solids content of the composition.

14. An improved bowling pin highly resistant to dirt pick-up carrying asa surface coating a substantially pigment and resin-free cellulose nitrate composition comprising a cellulose nitrate and an anti-dirtcollecting agent consisting of a halide of an aliphatic long chainderivative of a heterocyclic nitrogen base in which the aliphaticradical contains between 10 and 18 carbon atoms and is linked directlywith the nitrogen atom in an amount between 0.02% and 0.2% by weight ofthe total solids content of the composition.

JOHN WALDO CLOUGH.

